Acylating agents, their salts, and lubricants and fuels containing the same

ABSTRACT

Oil-soluble carboxylic acid acylating agents are prepared by reacting a high molecular weight mono- or polycarboxylic acid with a sulfonating agent. The resulting acylating agents can be converted to acidic, neutral, or basic metal salts. Both the novel acylating agents and the salts are useful additives for lubricants and fuels and as intermediates for the preparation of other useful lubricant and fuel additives, particularly high molecular weight oil-soluble acylated nitrogen compositions and esters. The latter are prepared by reacting the acylating agents with, for example, alkylene polyamines or mono- or polyhydric alcohols.

United States Patent 1 Murphy [451 Apr. 3, 1973 [S4] ACYLATING AGENTS,THEIR SALTS, 2,974,152 3/1961 Schulze et al. ..260/400 AND 3,268,5638/1966 Shen et al .260/400 CONTAINING THE SAME Primary Examiner-ElbertL. Roberts [75] inventor! J M phy, ill0 gh y.0 0 Attorney-Roger Y. K.Hsu, William H. Pittman and [73] Assignee: The Lubrizol Corporation,James Adams Wrcklrffe, Ohio [57] ABSTRACT [22] Ffled: 1970 Oil-solublecarboxylic acid acylating agents are 21 App[ 4 39 prepared by reacting ahigh molecular weight monoor polycarboxylic acid with a sulfonatingagent. The Related U.S. Application Data resulting acylating agents canbe converted to acidic, neutral, .or basic metal salts. Both the novelacylating [62] g 1968' agents and the salts are useful additives forlubricants and fuels and as intermediates for the preparation of otheruseful lubricant and fuel additives, particularly [52] U.S.Cl ..260/400,252/33 high molecular weight oil soluble acylated nitrogen [51] 143/90compositions and esters. The latter are prepared by of Search reactingthe acylating agents for example 31.

kylene polyamines or monoor polyhydric alcohols. [56] References CitedUNITED STATES PATENTS 13 Claims, No Drawings 3,268,563 8/1966 Shen et al..260/400 preparation of other useful compositions. In particular,

the invention relates to oil-soluble, high molecular weight, monoandpolycarboxylic acid acylating agents produced by reacting a carboxylicacid or a acylating derivative thereof with a sulfonating agent, thesalts of these acylating agents, and to lubricants and fuels containingthe acylating agents or their salts.

As well-known, high molecular weight carboxylic acid acylating agentscontaining at least about 30 and, preferably at least about 50,aliphatic carbon atoms are used as additives for lubricant and fuelcompositions, and as intermediates for the preparation of other productswhich are also useful as additives in lubricants and fuels. For example,U.S. Pat. Nos. 3,163,603; 3,219,666; 3,240,575; 3,271,310; and 3,272,746disclose useful sludge-dispersing materials prepared by reacting theseacids with various amines, metal compounds, or combinations of aminesand metal compounds; No. 3,288,714 discloses the use of a high molecularweight carboxylic acid anhydride as a lubricant additive; No. 3,331,776discloses esters prepared from such acids as additives for lubricants;and No. 3,346,354 discloses such acids, their anhydrides, and

I the esters thereof as fuel additives.

While the high molecular weight carboxylic acid acylating agents of thepresent invention can be used for the. same purposes as these prior-artcarboxylic acid acylating agents, they are particularly useful in thepreparation of metal salts which function as detergents and rustinhibitors in lubricants andfuels. The acylating agents and salts ofthis invention are described in more detail hereinbelow.

In accordance with the foregoing,-it is a principal object of thisinvention .to provide novel, high molecular weight, oil-solublecarboxylic acid acylating agents.

Another object of this invention is to provide novel, salts ofhigh-molecular weight carboxylic acids.

A further object is to provide lubricant and fuel compositionscontaining the acylating agents of this invention. a

A still further object is to provide lubricant and fuel compositionscontaining the salts.

These and other objects of this invention are achieved by providingoil-soluble carboxylic acid acylating agents which are reaction productsproduced by the process comprising reacting (A) at least one oilsolublehigh molecular weight monoor polycarboxylic acid acylating agentcharacterized by the presence within its structure of at least aboutthirty aliphatic carbon atoms exclusive ofcarboxyl carbon atoms with (B)at least one sulfonating agent,'the amounts of (A) and (B) employedbeing such that there is at least one mole of (B) for each mole of (A)in the reaction mixture, and the corresponding acidic, neutral or basicsalts of the acylating agents. The lubricant and fuel compositionscontemplated are those which contain the novel acylating agents andmetal salts of this invention.

As mentioned above, the carboxylic acid acylating agents used asintermediates in the preparation of the acylating agents of thisinvention are well known in the art. One important aspect of theseintermediates is that they should be substantially saturated, i.e., atleast about percent of the total number of the carbon-tocarbon covalentlinkages therein preferably should be saturated linkages. In anespecially preferred aspect of the invention, at least about 98 percentof these covalent linkages are saturated. Obviously, all of the covalentlinkages may be saturated. Agreater degree of unsaturation renders theacylating agents more susceptible to oxidation, degradation, andpolymerization and this lessens the effectiveness of the final productsas lubricant and fuel additives.

In addition, the intermediate acylating agents should be substantiallyfree from oil-solubilizing pendant groups, that is, groups having morethan about six aliphatic carbon atoms. Although, some suchoil-solubilizing pendant groups may be present, they preferably will notexceed one such group for every twenty-five aliphatic carbon atoms inthe principal hydrocarbon chain vof the acylating agent.

The intermediates may contain polar substitutents provided that thepolar substituents'are not present in proportions sufficiently large toalter significantly the hydrocarbon character of the radical.Illustrative polar substituents'are halo, such as chloro and bromo, oxo,oxy, formyl, sulfonyl sulfinyl, thio, nitro, etc. These polarsubstituents, if present, preferably will not exceed vl0 percent byweight of the total weight of the hydrocarbon portion of the carboxylicacid radical exclusive of the carboxyl group.

Carboxylic acid acylating agents suitable as intermediates for preparingthe acylating agents of this invention are well-known in the art andhave been described in detail, for example, in U.S. Pat. Nos. 3,087,936;3,163,603; 3,172,892; 3,189,544; 3,272,746; 3,288,714; 3,306,907;3,331,776; 3,340,281; 3,341,542; and 3,346,354. In the interest ofbrevity, these patents are incorporated herein for their disclosure ofthese monoand polycarboxylic acid acylating agents.

. As disclosed in the foregoing patents, there are several processesforpreparing the acylating agents used as starting materials. Generally,the process involves the reaction of (1) an ethylenically unsaturatedcarboxylic acid, acid halide, or a'nhydridewith (2) an ethylenicallyunsaturated hydrocarbon containing at least about 50'aliphatic carbonatoms or a chlorinated hydrocarbon containing at least about 50aliphatic carbon atoms at a temperature within the range of about100-300 C. The chlorinated hydrocarbon or ethylenically unsaturatedhydrocarbon reactant can, of course,-

contain polar substituents, oil-solubilizing pendant groups, and beunsaturated within the general limitations explained hereinabove.

.When preparing the. carboxylic acid acylating agent according to one ofthese two processes, the carboxylic acid reactant usually corresponds tothe formula R,- (COOH)n, where R is characterized by the presence of atleast one ethylenically unsaturated carbon-to-carbon covalent bond and nis an integer from one to six and preferably one or two. The acidicreactant can also be the corresponding carboxylic acid halide, an-

hydride, ester, or other equivalent acylating agent and mixtures of oneor more of these. Ordinarily, the total number of carbon atoms in theacidic reactant will not exceed ten and generally will not exceed six.Preferably the acidic reactant will have at least one ethylenic linkagein an a,,B-position with respect to at least one carboxyl function.Exemplary acidic reactants are acylic acid, methacrylic acid, maleicacid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride,citraconic acid, citraconic anhydride, mesaconic acid, glutaconic acid,chloromaleic acid, aconitic acid, crotonic acid, methylcrotonic acid,sorbic acid, 3-hexenoic acid, IO-decenoic acid, and the like. Due toconsiderations of economy and availability, these acid reactants usuallyemployed are acrylic acid, methacrylic acid, maleic acid, and maleicanhydride.

As is apparent from the foregoing discussion, the carboxylic acidacylating agents used as starting materials may contain cyclic and/oraromatic groups. However, the acids are substantially aliphatic innature and, in most instances, the preferred acid acylating agents arealiphatic, especially aliphatic monoand polycarboxylic acids,anhydrides, and halides.

The substantially saturated aliphatic hydrocarbonsubstituted succinicacid and anhydrides are particularly preferred as acylating agents foruse in the preparation of the novel acylating agents of the presentinvention. These succinic acid acylating agents are readily prepared byreacting maleic anhydride with a high molecular weight olefin or achlorinated hydrocarbon such as a chlorinated polyolefin. The reactioninvolves merely heating the two reactants at a temperature of aboutl-300 C., preferably, 100200 C. The produce from such a reaction is asubstituted succinic anhydride where the substituent is derived from theolefin or chlorinated hydrocarbon as described in the above citedpatents. The product may be hydrogenated to remove all or a portion ofany ethylenically unsaturated covalent linkages by standardhydrogenation procedures, if desired. The substituted succinicanhydrides may be hydrolyzed by treatment with water or steam to thecorresponding acid and either the anhydride or the acid may be convertedto the corresponding acid halide or ester by reacting with phosphorushalide, phenols, or alcohols.

The ethylenically unsaturated hydrocarbon reactant and the chlorinatedhydrocarbon reactant used in the preparation of the acylating agents areprincipally the high molecular weight, substantially saturated petroleumfractions and substantially saturated olefin polymers and thecorresponding chlorinated products. The polymers and chlorinatedpolymers derived from mono-olefins having from two to about thirtycarbon atoms are preferred. The especially useful polymers are thepolymers of l-mono-olefins such as ethylene, propene, l-butene,isobutene, l-hexene, --octene, 2- methyH-heptene, 3-cyclohexyl-l-butene,and 2- methyl-S-propyl-l-hexene. Polymers of medial olefins, i.e.,olefins in which the olefinic linkage is not at the terminal position,likewise are useful. These are exemplified by 2-butene, B-pentene, and4-octene.

The interpolymers of l-mono-olefms such as illustrated above with eachother and with other interpolymerizable olefinic substances such asaromatic olefins, cyclic olefins, and polyolefins, are also usefulsources of the ethylenically unsaturated reactant. Such interpolymersinclude for example, those prepared by polymerizing isobutene withstyrene, isobutene with butadiene, propene with isoprene, propene withisobu- 5 tene, ethylene with piperylene, isobutene with chloroprene,isobutene with pmethyl-styrene, l-hexene with l,3-hexadiene, l-octenewith l-hexene, 1- heptene with l-pentene, 3-rnethyl-l-butene withl-octene, 3,3-dimethyl-l-pentene with l-hexene, isobutene with styreneand piperylene, etc.

For reasons of oil-solubility and stability, the interpolymerscontemplated for use in preparing the acylating agents of this inventionshould be substantially aliphatic and substantially saturated, that is,they should contain at least about 80 percent and preferably about 95percent, on a weight basis, of units derived from aliphaticmono-olefins. Preferably, they will contain no more than about 5 percentolefinic linkages based on the total number of the carbon-to-carboncovalent linkages present.

The chlorinated hydrocarbons and ethylenically unsaturated hydrocarbonsused in the preparation of the acylating agents can have molecularweights of from about 700 up to about 100,000 or even higher. Thepreferred reactants are the above described polyolefins and chlorinatedpolyolefins having an average molecular weight of about 700 to about5,000. When the acylating agent has a molecular weight in excess ofabout 10,000, the acylated nitrogen composition also possess viscosityindex improving qualities.

In lieu of the high molecular weight hydrocarbons and chlorinatedhydrocarbons discussed above, hydrocarbons containing activating polarsubstituents which are capable of activating the hydrocarbon molecule inrespect to reaction with an ethylenically unsaturated acid reactant maybe used in the above-illustrated reactions for preparing the acylatingagents. Such polar substituents include sulfide and disulfide linkages,and nitro, mercapto, carbonyl, and formyl radicals. Examples of thesepolar-substituted hydrocarbons include polypropene sulfide,di-polyisobutene disulfide, nitrated mineral oil, di-polyethylenesulfide, brominated polyethylene, etc.

The intermediate acylating agents may also be prepared by halogenating ahigh molecular weight hydrocarbon such as the above described olefinpolymers to produce a poly-halogenating product, converting thepoly-halogenated product to a poly-nitrile, and then hydrolyzing thepoly-nitrile. They may be prepared by oxidation of a high molecularweight polyhydric alcohol with potassium permanganate, nitric acid, or asimilar oxidizing agent. Another method for preparing suchpoly-carboxylic acids involves the reaction of an olefin or apolar-substituted hydrocarbon such as a chloropolyisobutene with anunsaturated polycarboxylic acid such as Z-pentene-l ,3,5- tri-carboxylicacid prepared by dehydration of citric acid. Mono-carboxylic acidacylating agents may be obtained by oxidizing a monoalcohol withpotassium permanganate or by reacting a halogenated high molecularweight olefin polymer with a ketene. Another convenient method forpreparing monocarboxylic acid involves the reaction of metallic sodiumwith an acetoacetic ester or a malonic ester of an alkanol to form asodium derivative of the ester and the subsequent reaction of the sodiumderivative with a halogenated high molecular weight hydrocarbon such asbrominated wax or brominated polyisobutene.

Mono-carboxylic and poly-carboxylic acid intermediates can also beobtained by reacting chlorinated monoand polycarboxylic acids,anhydrides, acyl halides, and the like with ethylenically unsaturatedhydrocarbons or ethylenically unsaturated substituted hydrocarbons suchas the polyolefins and substituted polyolefins described hereinbefore inthe manner described in US. Pat. No. 3,340,281.

The mono-carboxylic and poly-carboxylic acid anhydrides are obtained bydehydrating the corresponding acids. Dehydration is readily accomplishedby heating the acid to a temperature above about 70 C., preferably inthe presence of a dehydration agent, e.g. acetic anhydride. Cyclicanhydrides are usually obtained from poly-carboxylic acids having acidradicals separated by no more than three carbon atoms such assubstituted succinic or glutaric acid, whereas linear anhydrides areobtained from poly-carboxylic acids having the acid radicals separatedby four or more carbon atoms. The acid halides of the mono-carboxylicand polycarboxylic acids can be prepared by the reaction of the acids ortheir anhydrides with a halogenating agent such as phosphorustribromide, phosphorus pentachloride, or thionyl chloride.

The acylating agent of this invention can be prepared by reacting atleast one high molecular weight carboxylic acid acylating agent of thetype described more fully hereinabove with a suitable sulfonating agentsuch as sulfur trioxide, sulfuric acid, a combination of sulfuric acidand thionyl chloride, a halosulfonic acid, and the like underconventional sulfonation conditions. These and other sulfonating agentsare well-known'in the art and the conditions under which they may beemployed are also known. For example, these sulfonating agents andconditions for their employment are discussed in detail in E. E.Gilbert, Sulfonation and Related Reactions, published by lntersciencePublishers, a division of John Wiley and Sons, Inc. New York (1965). Forthe sake of brevity, this text is incorporated herein ,by reference forits disclosure of sulfonating agents and conditions.

The preferred sulfonating agents are the halosulfonic acids of theformula where X is F or Cl. The most preferred sulfonating agentischlorosulfonic acid.

The reaction between the carboxylic acid acylating agent used as astarting material and the halosulfonic acid can be conducted over a widetemperature range, for example, from about 0C. to about 200C. However,the reaction proceeds readily at temperatures of about 25-l507 C.Temperatures of about 40-90 C. have been found to produce excellentresults in most cases and, for that reason, are preferred. The reactionis generally conducted in the presence of one or'more inert organicliquid diluents such as mineral oil, naphthas, ethcrs, the liquidhydrocarbons such as pentanc, hexane, heptane, cyclohexane, benzene,toluene,

xylene, and the corresponding chlorinated hydrocarbons.

The precise nature of the reaction products is not known. It is believedthat the sulfonating agents react with the acylating agents to formsulfo substituents on the carboxylic acid acylating agent. For example,if the carboxylic acid acylating agent used as a starting material is apolyisobutenyl-substituted succinic anhydride, reaction with asulfonating agent is believed to produce sulfo groups on thepolyisobutenyl substituent. However, it is also possible that otherproducts are produced. For example, when a halosulfonic acid isemployed, the reaction can result in substituents such as sulfonylhalides or a halosulfate substituent Moreover, when the carboxylic acidacylating agent used as the starting material is a carboxylic acidanhydride, it is possible that some halosulfonic acid can react to forma carboxylic-sulfuric acid anhydride, particularly at lower reactiontemperatures, e. g. S 0 C.:

Accordingly, the products of this invention are best described in termsof the process by which they are produced. It is possible that thereaction product is, in fact, a mixture of such carboxylic acidacylating agents.

Usually at least about one mole of the sulfonating agent is employed inthe reaction mixture for each mole of high molecular weight carboxylicacid-acylating agents used as a starting material. Of course, greateramounts of sulfonating agent can be used and, in most instances, atleast a slight molar excess of the sulfonating agent is desirable.However, for best results, there normally should not be more than onemole of sulfonating agent for each 25 aliphatic carbon atoms per mole ofcarboxylic acid acylating agent. Accordingly, the molar ratio ofsulfonating agent to carboxylic acid acylating agent should be such thatnot more than about one mole of sulfonating agent combines with. thecarboxylic acid acylating agent per 25 Example 1 briefly describes thepreparation of suitable carboxylic acid acylating agents suitable asstarting materials. The acylating agents are produced according to knownprocedures as described above.

Example 1 (A) A polyisobutenyl succinic anhydride having an acid numberof 105 and an equivalent weight of 540 is prepared by the reaction of achlorinated polyisobutylene having an average molecular weight of 1050and a chlorine content of 4.3 percent with maleic anhydride at 200 C.(B) A polypropenyl-substituted anhydride is prepared by the reaction ofa chlorinated polypropylene having a molecular weight of about 900 and achlorine content of about 4 percent with maleic anhydride at 200 C. Theproduct has an acid number of 75.

(C) A substituted succinic anhydride is prepared by reacting a maleicanhydride with a chlorinated copolymer of isobutylene and styrene. Thecopolymer consists of 94 parts of isobutylene units, 6 parts of styreneunits, has an average molecular weight of 1200, and a chlorine contentof 2.8 percent by weight. The resulting substituted succinic anhydridehas an acid number of 40.

(D) A substituted succinic anhydride is prepared by treating maleicanhydride with a chlorinated copolymer of isobutylene and isoprene. Thecopolymer consists of 99 parts of isobutylene units and one part ofisoprene units. The copolymer has a molecular weight of 28,000 and achlorine content of 1.95 percent. The resulting alkenyl-succinicanhydride has an acid number of 54.

(E) A polyisobutenyl-substituted succinic anhydride is prepared byreaction of a chlorinated polyisobutylene with maleic anhydride. Thechlorinated polyisobutylene has a chlorine content of 2 percent and anaverage molecular weight of 11,000. The polyisobutenyl-substitutedsuccinic anhydride thus produced has an acid number of 48.

(F) A methyl ester of a high molecular weight monocarboxylic acid isprepared by heatingan equi-molar mixture of a chlorinated polyisobutenehaving a molecular weight of 1000 and a chlorine content of 4.7 percentwith methyl methacrylate at 150-220 C.

(G) A substituted mono-carboxylic acid acylating agent is obtained byreacting at l50-200 C. an equimolar amount of acrylic acid and achlorinated polyisobutene having a chlorine content of about 4.5 percentand a molecular weight of about 850.

(H) A polyisobutene having a molecular weight of 1000 and maleicanhydride is heated at 150-220 C. to form a polyisobutenyl-substitutedsuccinic anhydride.

(I) A reaction mixture comprising 0.75 moles of polyisobutene having anaverage molecular weight of 1200 and 2.25 moles of chloroacetyl chlorideis refluxed in the presence of di-t-butyl peroxide accord ing to theprocedure described in US. Pat. No. 3,340,281 to produce a highmolecular weight carboxylic acid chloride.

Example 2 (A) A mixture of 1000 parts of mineral oil and 1650 parts ofpolyisobutenyl-substituted succinic anhydride (average molecularweight-825 prepared according to the procedure of Example 1(A) is heatedto about 65 C. Then 233 parts of chlorosulfonic acid are added over 1.5hours while maintaining the temperature at 65-75 C. The reaction mixtureis then blown with nitrogen for 2.5 hours while maintaining thetemperature at about C. The resulting reaction mixture is an oilsolution of the desired reaction product. This solution is characterizedby its sulfur content of 1.46 percent.

(B) A mixture comprising 1046 parts of polyisobutenyl-substitutedsuccinic anhydride (average molecular weight-l046) prepared according tothe procedure of Example 1(A) and 1046 parts of mineral oil is heated toabout 40 C. Thereafter, 128 parts of chlorosulfonic acid are added tothis mixture dropwise over a period of two hours while maintaining thetemperature of the mass at 40-50 C. The resulting reaction mixture isthen heated an additional two hours while maintaining a temperature of40-50 C. during which time it is blown with nitrogen. Subsequently, 6percent of Super Filtrol (a commercially available acidified clay usedas a filter aid and sold by Filtrol Corp.) is added and mixed for onehour and the entire mass filtered. The filtrate 'is an oil solution ofthe desired reaction product and is characterized by a sulfur content of0.62 percent.,

(C)A reaction mixture comprising 2112 parts ofpolyisobutenyl-substituted succinic anhydride (average molecularweight-1056) prepared according to the procedure of 1(A) and 570 partsof mineral oil is heated to 90 C. While maintaining this mixture at thattemperature, 233 parts of chlorosulfonic acid are added dropwise overtwelve hours. Thereafter, the reaction mixture is maintained at thistemperature for an additional two hours, the last hour of which thematerial is blown with nitrogen. A commercial filter aid is added andthe reaction mass filtered. The filtrate is an oil solution of thedesired reaction product and is characterized by a sulfur content of0.65 percent.

(D) 1036 parts of polyisobutenyl-substituted succinic anhydride (averagemolecular weight-1036) prepared according to the procedure of Example1(A) is heated to about 70-75 C. Thereafter, 245 parts of chlorosulfonicacid are added followed by 200 parts of mineral oil and 600 parts ofn-hexane during which time the temperature was lowered to 50 C.Thereafter,

this mixture is refluxed at 50 C. for three hours and then blown withnitrogen for four hours at a temperature of 50-60 C. to remove thehexane. The reaction mass is then filtered. The filtrate is an oilsolution of the desired reaction product and is characterized by itssulfur content of 2.9 percent.

(E) Six hundred and forty-five parts of polyisobute' nyl-substitutedsuccinic anhydride (average molecular weight-1300) prepared according tothe procedure of Example 1(H) and 645 parts of dichloroethylene aremixed at 21 C. and thereafter 122.5 parts of chlorosulfonic acid areadded during which time the temperature is maintained at 30-34 C. Thismixture is maintained at 30-40 C. for four hours while blowing withnitrogen. The material is stripped by heating to 68 C. at a pressure of10 mm. (Hg) and thereafter filtered. The filtrate is an oil solution ofthe desired reaction product and is characterized by a sulfur content of1.6 percent.

The following general procedures utilized in Exam- I ple 2, additionalreaction products contemplated by the present invention are prepared byusing the carboxylic acid acylating agent and sulfonating agentindicated in the following Table in the indicated amounts.

(A) 1056 parts of polyisobutenyl-substituted succinic anhydride (averagemolecular weight-1056) prepared according to the procedure of Example1(A) and 1056 parts of mineral oil are heated to 60 C. Thereafter, whilemaintaining a temperature of 60-75 C., 122 parts of chlorosulfonic acidis added over a two-hour period. The reaction mixture is then blown withnitrogen for one hour while maintaining a temperature at 70 C. Theresulting mixture is an oil solution of the desired reaction product.

(B) The use of the reaction products of this invention as acylatingagent intermediates for the preparation of nitrogen-containing sludgedispersants for lubricating oil compositions is illustrated as follows:A mixture comprising 907 parts of the above oil solution, 42 parts ofPolyamine H (an ethyleneamine mixture having an average compositioncorresponding to that of tetraethylene pentamine and available fromCarbide and Carbon) and 150 parts toluene are mixed at room temperature.This mixture is heated at about 150 C. for five hours. Subsequently,this reaction mixture is stripped at 150 C. and 20 mm. (Hg) pressure.The resulting product is adjusted to an oil content of about 47 percentproducing an oil-solution of the desired acylated amine dispersant. Theoil solution is characterized by a nitrogen content of 1.51 percent anda sulfur content of 0.96 percent. It can be employed in crankcaselubricating oils as a sludge dispersant in concentrations of about 0.01percent to about 20 percent by weight although it will normally be usedin amounts of about 0.1 percent to about 5 percent.

As will be apparent to those skilled in the art, additional inertorganic liquid diluents can be used in the foregoing reactions tofacilitate mixing and filtering in those cases where the reactants orthe products are so viscous as to make handling and filtering difficult.While the foregoing examples illustrate the preferred embodiment of theinvention, that is, the reaction products prepared from chlorosulfonicacid and fluorosulfonic acid, it is clear that other conventionalsulfonating agents discussed hereinabove can be substituted for thesehalosulfonic acids in the foregoing examples on an equal molar basisusing the techniques suggested by Gilbert, supra, to produce otherproducts of the type contemplated by the present invention.

As mentioned above, the metal salts of the above reaction products arealso contemplated by the present invention, particularly the Group 1,Group II, aluminum, lead, tin, cobalt, and nickel metal salts. The metalsalts can be acidic salts, neutral salts, or basic salts.

As is apparent, the reaction products of this invention arecharacterized by the presence of an average of at least about two acidicgroups per molecule, one acidic group being a carboxyl group orfunctional derivative thereof (i.e., anhydride, carboxylic acid ha.-lide, carboxylic acid ester) and the other being the sulfur-containingacidic group formed from the sulfonating agent. Accordingly, it ispossible to prepare acidic salts of the reaction products of thisinvention, that is, salts in which all of the acyl groups present in themolecules of the reaction product have not combined with metal to form ametal salt. In other words, acidic salts are those metal salts whichcontain less metal than that amount required to neutralize all theacidic groups present according to known principles of stoichiometry.Such salts will be illustrated by the following illustrative formulas:

ll HO Polyisobuten yl} CO-Metal Of course, if the carboxylic acidacylatingagent from which the reaction products are prepared arepolycarboxylic acid acylating agents, other acidic salts are possible.For example:

It should be understood that the foregoing formulas are reactant metalcompound with the reaction products, that is, one equivalent of metalfor each equivalent of carboxyl, sulfo, etc. present in the reactionmixture.

A basic salt is a salt in which the metal is present instoichiometrically greater amounts that that required to neutralize theacid groups present. Such basic salts are characterized by a metalratio' greater than one. The term metal ratio as used herein is theratio of the total equivalents of metal in the salts to the equivalentsof acid therein. Thus, it is a measure of the stoichiometric excess ofmetal in a metal salt of the acid. For example, a basic salt can beobtained by the reaction of 1.1 to 2.0 equivalents of a basicallyreacting metal compound with each equivalent of acid present in thereaction product according to known procedures.

In preparing basic metal salts, it is sometimes advantageous to treatthe reaction mixture, in the presence of a promoter, with carbon dioxideor other acidic material at a temperature within the range of from about20 C. to the reflux temperature of the mixture. Carbon dioxide isusually employed although such materials as H S, HCl, ,80 and the likecan be used. Such overbasing procedures are well-known in the prior art,see for example, US. Pat. Nos. 2,616,904; 2,616,905; 2,616,911;2,616,924; 3,027,325; 3,170,880; 3,170,881; 3,312,618, and the like. Thepromoters which are normally used in the overbasing processes are thelower alcohols, e.g., methanol, ethanol, propanol, isopropanol, mixturesof these, etc., and phenolic compounds particularly alkyl-substitutedphenols such as heptylphenol, octylphenol, nonylphenols, and the like.

For example, a basic barium salt of a reaction product of the presentinvention can be prepared by reacting the reaction product and bariumoxide in an equivalent ratio of acid groups to barium of 1:6 andcarbonating the mixture in the presence of heptylphenol. The carbonationstep is not absolutely necessary in preparing all basic salts, but it isbeneficial in that it allows the incorporation of significantly moremetal into the oil'soluble product and also has a clarifying effect onboth the process mixture and the ultimate product.

The carbon dioxide treatment is conducted in such a manner as to reducesubstantially the titratable basicity of the reaction mass. Thereare'essentially two materials in the reaction mass prior to carbonationwhich are susceptible to reaction with carbon dioxide: the free basicmetal compound (that which is in excess of the stoichiometric quantityrequired to form the normal metal salt) and the normal or neutral metalsalt. It is possible that each of these materials reacts with the carbondioxide simultaneously, but it is more likely that the excess basicmetal compound is carbonated first and then the normal metal salt iscarbonated last.

The metal salts of this invention can be prepared by mixing, at atemperature within the range of from about C. to about the refluxtemperature, a basically reacting metal compound and areaction productaccording to the invention. In order to form the salts, the acid groupsof the reaction product preferably should be in the acid form, i.e.,carboxyl groups, sulfo groups, and etc. This is readily accomplished byknown techniques. For example, carboxylic acid anhydrides can beconverted to the corresponding acids by hydrolysis. Of course, this canbe accomplished in situ. That is, a reaction product containingcarboxylic acid anhydride groups can be reacted with the basicallyreacting metal compound in the presence of water so that the anhydrideis converted to the corresponding acid in the reaction mixture.

The metal salts can also be prepared by a double decomposition reaction.That is, the reaction product can be reacted with a basic alkali metalcompound and the resulting alkali metal salt can then be reacted with ametal halide to produce a given metal.

It is usually desirable to conduct the reaction in the presence ofsubstantially inert organic diluents of the type described hereinabovewith regard to preparation of the reaction products themselves. Alcoholsincluding high molecular weight alcohols such as isooctyl alcohols alsoare useful diluents in the preparation of salts.

The basically reacting metal compounds suitable for preparing the saltsof this invention are the usual metal reactants normally employed toprepare acid salts such as metal oxides, metal hydroxides, metalalcoholates, metal carbonates, and the like. Specific examples includethe following: lithium oxide, lithium hydroxide, lithium carbonate,lithium pentylate, sodium oxide, sodium hydroxide, sodium carbonate,sodium methylate, sodium propylate, sodium phenoxide, potassium oxide,potassium hydroxide, potassium carbonate, potassium methylate, silveroxide, silver carbonate, magnesium oxide, magnesium hydroxide, magnesiumcarbonate, magnesium ethylate, magnesium propylate, magnesium phenoxide,calcium oxide, calcium hydroxide, calcium carbonate, calcium methylate,calcium propylate, calcium pentylate, zinc oxide, zinc hydroxide, zinccarbonate, zinc propylate, strontium oxide, strontium hydroxide, cadmiumoxide, cadmium hydroxide, cadmium carbonate, cadmium ethylate, bariumoxide, barium hydroxide, barium hydrate, barium carbonate, bariumethylate, barium pentylate, aluminum oxide, aluminum propylate, leadoxide, lead hydroxide, lead carbonate, tin oxide, tin butylate, cobaltoxide, cobalt hydroxide, cobalt carbonate, cobalt pentylate, nickeloxide, nickel hydroxide,-and nickel carbonate. This invention is notlimited to the use of these metal compounds as they are presented merelyto exemplify metal compounds suitable for preparing the salts of thisinvention.

Example 12 A sodium salt of the reaction product of Example 2(A) isprepared by heating 2694 parts of the reaction product to about C. andthereafter adding aqueous sodium hydroxide (50 parts of sodium hydroxidedissolved in parts of water) to the reaction product. This mixture isstirred and then 600 parts of toluene are added. Thereafter water isremoved from the react on mixture by distillation. The resulting mixtureis an oil solution of an acidic sodium salt of the reaction product ofExample 2(A).

To this oil-solution there is added 129 parts of Polyamine H over a onehour period during which time the temperature of the mixture increasesfrom 30 C. to 60 C. The resulting mixture is refluxed until 28 parts ofwater are removed from the reaction mass. The remaining toluene isremoved by stripping the mixture to a temperature of 150 C. at apressure of 25 mm. (Hg) and the mixture is filtered. The filtrate is anoil solution of an acylated nitrogen compound useful as a dispersant inlubricating oils. The filtrate is characterized by a sodium sulfate ashcontent of 0.87 percent and a sulfur content of 0.81 percent.

Example 13 (A) A reaction mixture comprising 1110 parts ofpolyisobutenyl-substituted succinic anhydride (average molecularweight-1110) prepared according to the process of Example 1(A) and 1000parts of mineral oil are heated to 35 C. Then 122 parts ofchlorosulfonic acid are added over a 2.5-hour period while maintainingthe temperature at 3545 C. The resulting mixture is then maintained atabout 35 C. for two hours while blowing with nitrogen. This mixture isan oil solution of the desired reaction product and is characterized bya sulfur content of 1.26 percent. (B) An additional 300 parts of mineraloil and 200 parts of water and 153 parts of calcium hydroxide are addedto the thus produced oil solution and the resulting mixture is refluxedfor one hour. Thereafter the reaction mass is heated to 150 C. to removewater. The resulting product is very viscous so '650 parts of mineraloil, 75

parts of isooctyl alcohol, and benzene are added to facilitatefiltration. After filtration, v the filtrate is stripped to atemperature of 150 C. at 20 mm. (Hg).

' The filtrate is an oil solution of the desired neutral calcium salt ofthe reaction product.

Example 14 A reaction product is prepared according to Example 2(B) andadjusted to an oil content of 37.2 percent. Then, 1200 parts of this oilsolution and 317 parts additional oil are mixed and heated to 60 C.Subsequently,

59 parts of lithium hydroxide monohydrate are added slowly whilemaintaining a temperatureof 60-70 C. Upon the completion of the additionof the lithium hydroxide monohydrate, the reaction mixture is heated at90-l00 C. for two hours and then dried by heating at- 150 C. for twohours with nitrogen blowing. The

. dried reaction mixture is then filtered. The filtrate has a lithiumsulfate ash content of 4.88 percent, a sulfur.

content of 0.687 percent, and is .an oil solution of the desired neutralsalt.

Example 15 150 C. with nitrogen blowing and filtered. .Thefiltrate is anoil solution of the desired neutral strontium salt.

Example 16 The procedure of Example 15 is repeated but an equivalentamount of zinc oxide is substituted for the strontium hydroxide therebyproducing the corresponding zinc salt.

Example 1 7 The procedure of Example 15 is followed but an equivalentamount of nickel carbonate is substituted for the strontium hydroxidethereby producing the corresponding nickel salt.

Example 18 To a reaction mixture comprising 1500 parts of a reactionproduct according to Example 2(B) which has been diluted to an oilcontent of 50 percent and contains 1.3 equivalents of acid, 500 parts oftoluene, 150 parts water, and 150 parts heptylphenol, there is added 650parts of barium oxide. The mixture is slowly heated to 150 C. andmaintained at this temperature under reflux while blowing with carbondioxide until the reaction mixture is substantially neutral. Thereafter,the mixture is dried at 150 C. and filtered, the filtrate being anoil-solution of the desired basic barium salt.

Example 19 To a mixture comprising 1500 parts of a reaction productprepared according to the procedure of Example 2(B) diluted to an'oilcontent of 50 percent and containing 1.3 equivalents of acid and 500parts of toluene there is added 175 parts of a 50 percent aqueoussolution of sodium hydroxide. This mixture is maintained at about 100 C.for two hours in order to remove water and thereafter filtered. To thedried filtrate there is added a solution of 120 grams of calciumchloride in 170 parts water. The resulting mixture is then maintained ata temperature of 100 C. for two hours. This mixture is then dried and240 parts of methanol and 120 parts of calcium hydroxide are added.While maintaining the temperature of this mixture at 50 C.,carbondioxide is blown therethrough until the mixture is substantiallyneutral. Subsequently, the reaction mixture is dried at 150 C. andfiltered. The filtrate is an oil-solution of the desired'basic calciumsalt.

The reaction products and salts of this invention can mixtures thereof.The lubricating compositions con.-

templated-include principally crankcase lubricating oils forspark-ignited and compression-ignited internal combustion enginesincluding automobile and truck engines, two-cycle engine lubricants,aviation piston engines, marine and railroad diesel engines, and thelike. However, automatic transmission fluids, transaxle lubricants, gearlubricants, metal-working lubricants, hydraulic fluids, and otherlubricating oil and grease compositions can benefit from theincorporation of the present additives.

Natural oils include animal oils and vegetable oils (e.g., castor oil,lard oil) as well as solvent-refined or acid-refined mineral lubricatingoils of the paraffinic, naphthenic, or mixed paraffinic-naphthenictypes. Oils of lubricating viscosity derived from coal or shale are alsouseful base oils. Synthetic lubricating oils include hydrocarbon oilsand halo-substituted hydrocarbon oils such as polymerized andinterpolymerized olefins (e.g., polybutylenes, polypropylenes,propylene-isobutylene' copolymers, chlorinated polybutylenes, etc.);alkyl benzenes (e.g., dodecylbenzenes, tetradecylbenzene,dinonyl-benzenes, di-(2-ethylhexyl)benzenes, etc.); polyphenyls (e.g.,biphenyls, terphenyls, etc.); and the like. Alkylene oxide polymers andinterpolymers and derivatives thereof where the terminal hydroxyl groupshave been modified by esterification, etherification, etc., constituteanother class of known synthetic lubricating oils. These are exemplifiedby the oils prepared through polymerization of ethylene oxide orpropylene oxide, the alkyl and aryl ethers of these polyoxyalkylenepolymers (e.g., methylpolyisopropylene glycol ether having an averagemolecular 'weight of 1000, diphenyl ether of polyethylene glycol havinga molecular weight of 500-1000, diethyl ether of polypropylene glycolhaving a molecular weight of 1000-1500, etc.) or mono-and polycarboxylicesters thereof, for example, the acetic acid esters, mixed C -C fattyacid esters, or the C oxo acid diester of tetraethylene glycol. Anothersuitable class of synthetic lubricating oils comprises the esters ofdicarboxylic acids (e.g., phthalic acid, succinic acid, maleic acid,azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid,linoleic acid dimer, etc.) with a variety of alcohols (e.g., butylalcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol,pentaerythritol, etc). Specific examples of these esters includesdibutyl adipate, di(2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctylsebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate,didecyl phthalate, dieicosyl sebacate, the 2-ethylhexyl diester oflinoleic acid dimer, the complex ester formed by reacting one mole ofsebacic acid with two moles of tetraethylene glycol and two moles of2-ethyl-hexanoic acid, and the like.

'Silicon-based oils such as the polyalkyl-, polyaryl-,

polyalkoxy-, or polyaryloxy-siloxane oils and silicate oils compriseanother useful class of synthetic lubricants (e.g., tetraethyl-silicate,tetraisopropyl-silicate, tetra-(2-ethylhexyl)-silicate,tetra-(4-methy1-2-tetraethyl)-silicate,tetra-(p-tert-butylphenyl)-silicate,hexyl-(4-methyl-2-pentoxy)-disiloxane, poly(methyl)- siloxanes,poly(methyl-phenyl)-siloxanes, etc.). Other synthetic lubricating oilsinclude liquid esters of phosphorus-containing acids (e.g., tricresylphosphate, trioctyl phosphate, diethylester of decane phosphonic acid,etc.), polymeric tetrahydrofurans, and the like.

The reaction products and salts of this invention can also be used asadditives for normally liquid fuels such as those used in furnaces andinternal combustion engines. When used as fuel additives, thesematerials promote cleanliness of metal parts with which they come intocontact. For example, when used in internal combustion engines, theadditives of this invention promote cleanliness of the fuel systemincluding the carburetor, fuel tank, and the like. Moreover, theirpresence in the fuels appears to lessen the tendancy of solid depositformation in the exhaust system. In addition, the metal salts,particularly the basic metal salts of the alkaline earth metals helpreduce the formation of black exhaust smoke upon combustion whenincorporated in fuels for diesel engines.

Ordinarily, the reaction products and salts of this invention will beemployed in the fuels in amounts such as they will comprise from about0.001 percent to about percent by weight of the total fuel composition.Preferably, the additives will be present in amounts of Example A SAElOW-30 mineral lubricating oil containing 5% of the reaction product ofExample 2(A), 0.075 percent of phosphorus as zincdi-n-octylphosphorodithioate, and 5 percent of the barium salt of anacidic composition prepared by the reaction of 1000 parts of apolyisobutene having the molecular weight of 60,000 with 10 parts ofphosphorus pentasulfide at 200 C. and hydrolyzing the product with steamat 150 C.

Example B SAE lOW-30 mineral lubricating oil containing 1.5 percent ofthe product of Example 2(C) and 0.05 percent of phosphorus as the zincsalt of a phosphorodithioic acid prepared by the reaction of phosphoruspentasulfide with a mixture of 60 percent (mole) of p-butylphenol and 40percent (mole) of npentyl alcohol.

Example C SAE 20 mineral lubricating oil containing 2 percent of theproduct of Example 2(E).

Example D SAE 10 mineral lubricating oil containing 1.5 percent of theproduct of Example 1(D), 0.075 percent phosphorus as the adduct obtainedby heating zinc dinonylphosphorodithioate with 0.25 moles of1,2-hexeneoxide at C., a sulfurized methylester of tall oil acid havinga sulfur content of 15 percent, 6 percent of a polybutene viscosityindex improver having an average molecular weight of 80,000100,000, and0.05 percent of lard oil.

Example E Methyl polyisopropylene glycol ether (average molecularweight-1000) lubricating oil containing 1 percent of the product ofExample 4.

Example F SAE 30 mineral lubricating oil containing 6 percent of theproduct of Example 10, 0.075 percent of phosphorus as the zinc salt ofphosphorodithioic acid prepared by the reaction of phosphoruspentasulfide with an equi-molar mixture of n-butyl alcohol .and dodecylalcohol, and 3 percent of a barium detergent prepared by carbonating amineral oil solution containing one mole of sperm oil, 0.6 mole ofoctylphenol, 2 moles of barium oxide, and a small amount of water at C.

ExampleG ing mineral oil, calcium mahogany sulfonate, and 6 moles ofcalcium hydroxide in the presence of an equimolar mixture (10 percent ofthe mixture) of methyl alcohol and n-butyl alcohol as a promoter at thereflux temperature.

Example H Diesel fuel containing 0.2 percent of the product of Example19.

Example I Gasoline containing 0.05 percent of the product of Example2(A).

Example J Kerosene containing 0.5 percent of the product of Example2(E).

As is apparent in the foregoing illustrative examples, it iscontemplated that the lubricants and fuel compositions of the presentinvention will contain other conventional additives. Such additivesinclude for example, detergents of the ash-containing type prepared fromoil soluble sulfonic acids, viscosity index improving agents, pour pointdepressing agents, anti-foam agents, extreme pressure agents,rust-inhibiting agents, and other oxidation and corrosion inhibitingagents. Such additives are well-known in the art and need no detaileddescription herein. Examples of these materials are given in theforegoing examples and are discussed in many of the patents which havebeen incorporated herein by reference.

Similarly, the fuel compositions of this invention will containadditional additives such as deicers, lead scavengers, leadappreciators, demulsifiers, lead alkyl anti-knock additives, and thelike, allof which are wellknown in the art.

What is claimed is:

1. An oil-soluble carboxylic acid acylating agent which is the reactionproduct produced by reacting under sulfonation conditions at atemperature of about 0 C. to about 200 C. (A) at least one oil-solublesubstantially saturated high molecular weight succinic acid acylatingagent characterized by the presence within its structure of at leastabout 50 aliphatic carbon atoms exclusive of the carboxyl carbon atomsand selected from the class consisting of anhydrides, esters, andhalides with (B) at least one sulfonating agent, the amounts of (A) and(B) employed being such that there is at least about one mole of (B) foreach mole of (A) in the reaction mixture and up to about one mole of (B)for each 25 aliphatic carbon atoms per mole of (A), wherein (A) isproduced by the process comprising reacting (l) maleic acid, anhydride,ester. or acid halide with (2) ethylenically unsaturated hydrocarboncontaining at least about 50 aliphatic carbon atoms or a chlorinatedhydrocarbon containing at least about 50 aliphatic carbon atoms at atemperature within the range of about -300 C.

2. An oil-soluble carboxylic acid acylating agent according to claim 1wherein (A) is prepared by reacting maleic acid or anhydride with apolyolefin or chlorinated polyolefin having an average molecular weightof about 700 to about 5000.

3. An oil-soluble carboxylic acid acylating agent according to claim 2wherein (B) is selected from the class consisting of chlorosulfonicacid, flurosulfonic acid, or mixtures thereof and the sulfonationreaction temperature is in the range of about 25l 50 C.

4. An oil-soluble carboxylic acid acylating agent according to claim 3wherein (A) is formed by reacting a polymer of l-monoolefin or achlorinated polymer of 1- monoolefin with maleic acid or anhydride.

5. An oil-soluble carboxylic acid acylating agent according to claim 4wherein (B) is chlorosulfonic acid.

6. An oil-soluble carboxylic acid acylating agent according to claim 5wherein (A) is formed by reacting polyisobutylene or chlorinatedpolyisobutylene with at least one member selected from the classconsisting of maleic acid, maleic anhydride.

7. An oil-soluble acidic, neutral, or basic metal salt of an acylatingagent according to claim 1 the metal cations of said salt being selectedfrom the class consisting of aluminum, lead, tin, cobalt, nickel, GroupI and Group II metal cations.

8. An oil-soluble acidic, neutral, or basic metal salt of an acylatingagent according to claim 3, wherein the metal cation is selected fromthe class consisting of aluminum, lead, tin, cobalt, nickel, Group I andGroup 11 metal cations.

9. An oil-soluble acidic, neutral, or basic metal salt from an acylatingagent according to claim 4 wherein the metal cation is selected fromthe'group consisting of lithium, strontium, magnesium, calcium", barium,and zinc cations.

10. An oil-soluble acidic, neutral, or basic metal salt of an acidicreactant according to claim 6 wherein the metal cation is selected fromthe group consisting of lithium, strontium, magnesium, calcium, barium,and zinc cations.

11. An oil-soluble salt according to claim 10 which is an acidic salt.

12. An oil-soluble salt according to claim 10 which is a neutral salt.

13. An oil-soluble salt according to claim 10 which is a basic salt.

2. An oil-soluble carboxylic acid acylating agent according to claim 1wherein (A) is prepared by reacting maleic acid or anhydride with apolyolefin or chlorinated polyolefin having an average molecular weightof about 700 to about
 5000. 3. An oil-soluble carboxylic acid acylatingagent according to claim 2 wherein (B) is selected from the classconsisting of chlorosulfonic acid, flurosulfonic acid, or mixturesthereof and the sulfonation reaction temperature is in the range ofabout 25*-150* C.
 4. An oil-soluble carboxylic acid acylating agentaccording to claim 3 wherein (A) is formed by reacting a polymer of1-monoolefin or a chlorinated polymer of 1-monoolefin with maleic acidor anhydride.
 5. An oil-soluble carboxylic acid acylating agentaccording to claim 4 wherein (B) is chlorosulfonic acid.
 6. Anoil-soluble carboxylic acid acylating agent according to claim 5 wherein(A) is formed by reacting polyisobutylene or chlorinated polyisobutylenewith at least one member selected from the class consisting of maleicacid, maleic anhydride.
 7. An oil-soluble acidic, neutral, or basicmetal salt of an acylating agent according to claim 1 the metal cationsof said salt being selected from the class consisting of aluminum, lead,tin, cobalt, nickel, Group I and Group II metal cations.
 8. Anoil-soluble acidic, neutral, or basic metal salt of an acylating agentaccording to claim 3, wherein the metal cation is selected from theclass consisting of aluminum, lead, tin, cobalt, nickel, Group I andGroup II metal cations.
 9. An oil-soluble acidic, neutral, or basicmetal salt from an acylating agent according to claim 4 wherein themetal cation is selected from the group consisting of lithium,strontium, magnesium, calcium, barium, and zinc cations.
 10. Anoil-soluble acidic, neutral, or basic metal salt of an acidic reactantaccording to claim 6 wherein the metal cation is selected from the groupconsisting of lithium, strontium, magnesium, calcium, barium, and zinccations.
 11. An oil-soluble salt according to claim 10 which is anacidic salt.
 12. An oil-soluble salt according to claim 10 which is aneutral salt.
 13. An oil-soluble salt according to claim 10 which is abasic salt.